AB0436 EFFECTIVENESS OF BELIMUMAB IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS: A REAL-LIFE ANALYSIS
Authors: L. Picciariello, F. Ceccarelli, F. Natalucci, G. Olivieri, C. Pirone, V. Orefice, C. Garufi, F. R. Spinelli, R. Priori, C. Alessandri, F. Conti
Journal: Annals of the Rheumatic Diseases (2022)

Background Efficacy and safety of belimumab (BLM) in Systemic Lupus Erythematosus (SLE) patients with active disease have been demonstrated by RCTs [1,2] and confirmed by several observational studies [3-8]. Most of these data have been obtained by the use of BLM intravenous formulation (IV); on the contrary, very few findings are available on the use of the drug subcutaneous formulation (SC). Objectives Efficacy and drug survival of BLM have been assessed in a monocentric cohort of SLE patients, exploring any difference between the two routes of administration, IV or SC. Methods A longitudinal study on SLE patients (according to ACR 1997 classification criteria [9]) candidates for treatment with BLM has been performed. Demographic, clinical-laboratory and therapeutic data - including glucocorticoid dosage in prednisone-equivalent - have been collected. Disease activity has been assessed by SLEDAI-2k [10]; in patients with inflammatory articular involvement, DAS28-PCR [11] has been used. In compliance with the study protocol, patients were assessed at baseline and at 3 and 12 months after starting treatment. Results A total of 85 patients treated with BLM were enrolled, most of whom were female (male/female 2/83), with a median age of 48 years (IQR 13) and a median disease duration of 127 months (IQR 151). Fifty-one patients (60%) were treated with IV formulation and the remaining 34 (40%) with SC route. BLM was prescribed due to the following clinical manifestations: joint involvement (61.2%), cutaneous manifestations (20.0%), renal involvement (for residual proteinuria, 5.9%), haematological modifications (5.9%), constitutional involvement (3.5%), pericarditis (1.2%), headache (1.2%). In both the formulations, joint involvement was the most frequent indication of BLM (IV: 64.7%, SC: 58.8%). Median treatment duration was 15 months (IQR 24). Moving on drug efficacy, after 3 and 12 months of follow-up BLM has determined a significant reduction of SLEDAI-2k median values (p=0.001, p&lt;0.001 respectively, Figure 1A) as well as of daily prednisone dose (p=0.009, p&lt;0.0001 respectively, Figure 1B). In patients treated because of musculoskeletal manifestations, DAS28-PCR reduced significantly at 3 and 12 months after treatment (p&lt;0.0001). Drug survival at 12 months was 70% in the total cohort (Figure 1C) and was higher in patients treated with SC formulation than with IV route (75.8% versus 66.5%, p=ns). During the period of follow-up, 39 patients (45.9%) discontinued BLM: 38.4% of patients due to adverse events, 41% for primary or secondary inefficacy, 15% lost to follow-up, 5.1% for pregnancy. BLM withdrawal for adverse events was more frequent in the group of patients treated with IV formulation than SC one (25.9% versus 5.9%, p=0,0001). 11 patients switched from IV formulation to SC one after a median period of 40 months (IQR 20) without loss of efficacy or adverse events. Conclusion Our results confirm BLM efficacy also in a real-life setting. Notably, our data highlight a better drug survival in patients treated with SC formulation, mainly secondary to a less frequency of adverse events. References [1]Furie R et al. Arthritis Rheum. 2011;63(12):3918-3930. [2]Navarra SV et al. Lancet. 2011;377(9767):721-731. [3]Andreoli L et al. Isr Med Assoc J. 2014;16(10):651-653. [4]Hui-Yuen JS et al. J Rheumatol. 2015;42(12):2288-2295. [5]Collins CE et al. Lupus Sci Med. 2016;3(1):e000118. [6]Touma Z et al. Rheumatol Int. 2017;37(6):865-873. [7]Iaccarino L et al. Arthritis Care Res (Hoboken). 2017;69(1):115-123. [8]Gatto M et al. Arthritis Rheumatol. 2020;72(8):1314-1324. [9]Hochberg M.C. Arthritis Rheum. 1997;40:1725. [10]Gladman DD et al. J Rheumatol. 2002;29(2):288-291. [11]Prevoo ML et al. Arthritis Rheum. 1995;38(1):44-48. Disclosure of Interests None declared